Vaginal Infection Makes Women More Likely to Pass HIV to Men

July 18 (Bloomberg) -- Women who have both HIV and the most
common vaginal infection are more likely to transmit the AIDS-causing virus to uninfected men, a study found.

Men were three times more likely to contract HIV from their
female partners if the women also had bacterial vaginosis in the
three months before the men became infected, researchers led by
Craig Cohen from the University of California, San Francisco,
said at an AIDS meeting in Rome today.

The study is the first to show a link between HIV and an
infection that strikes as many as half of all African women.
While antibiotics can clear bacterial vaginosis, the disease
recurs in as many as 70 percent of women within three months,
Cohen said. He’s working with closely held Osel Inc., based in
Mountain View, California, on a product that would replenish
helpful bacteria in the vagina after antibiotics clear out the
harmful ones, helping to protect against repeat infections.

“By replenishing the good guys, you’re reducing the risk
of the bad guys coming back,” Cohen said in an interview today.

Cohen and colleagues recruited 2,236 HIV-negative men in
seven African nations whose female partners were HIV-positive.
Among those whose partners also had bacterial vaginosis, 2.9 men
in every 100 caught HIV over two years, compared with 0.9 men
per 100 whose partners were free of the disease. In men who
acquired HIV, the researchers matched the virus genetically to
their female partners to make sure they didn’t get it from
someone else.

Starpharma’s Gel

The study, funded by the Bill & Melinda Gates Foundation,
was presented at the International AIDS Society’s Conference on
HIV Pathogenesis, Treatment and Prevention in Rome today.

Cohen has also worked with Melbourne-based Starpharma
Holdings Ltd. on an experimental gel designed to cure women of
bacterial vaginosis. VivaGel, as the product is called, may be
used as an alternative to antibiotics in the $350 million market
for topical treatments against the infection.

In a study of 132 women who used VivaGel or a placebo every
night for a week, the product cleared bacterial vaginosis in 74
percent of women within two to five days, compared with 22
percent for those using the placebo, the company said in May.
It’s planning to test the gel in the third and final stage of
patient studies usually needed for regulatory approval, it said
at the time.

“This is powerful research that adds to my conviction that
Starpharma’s VivaGel product, which is highly effective at
dealing with bacterial vaginosis,” Stuart Roberts, an analyst
at Bell Potter Securities Ltd. in Sydney, said in an e-mail.
VivaGel “has a future role to play in limiting the spread of
HIV/AIDS in both the first and emerging worlds.”